Add plain C operation.

Submitted by Polch on Tue, 2010-12-07 17:31

Hi devs.

The manual says

Quote:

Using this mechanism, any method of any class can be added to a task's method interface, not just functions of a TaskContext You can also add plain C functions, just omit the this pointer.

So this code should work ?

#include <rtt/os/main.h>
 
#include <rtt/TaskContext.hpp>
 
struct Bar
{
  std::string foo(void) const
  {
    return "a string";
  }
};
 
 
std::string foo(void)
{
  return "a string";
}
 
int ORO_main(int argc, char** argv)
{
  RTT::TaskContext tc("test");
  Bar bar;
 
  tc.addOperation("foo"      , &foo     , 0   , RTT::ClientThread);
  tc.addOperation("Bar::foo" , &Bar::foo, &bar, RTT::ClientThread);
 
  return 0;
}

But i get

Quote:

error: no matching function for call to ‘RTT::TaskContext::addOperation(const char [4], std::string (*)(), int, RTT::ExecutionThread)’

Have you had this problem ? What is the correct way of adding a plain C function ?

Thanks for your help.

Paul.

Hello Peter.Thank you for

Submitted by Polch on Wed, 2010-12-08 07:56.

Hello Peter.

Thank you for your reply.

I've the same error by removing the third param. Moreover, i don't see the declaration of the function whithout the "third" param.

Paul.

Hello Peter.Thank you for

Submitted by Polch on Wed, 2010-12-08 07:53.

Hello Peter.

Thank you for your reply.

I've the same error by removing the third param. Moreover, i don't see the declaration of the function whithout the "third" param.

Paul.

Hello Peter.Thank you for

Submitted by peter on Wed, 2010-12-08 08:56.

On Wed, Dec 8, 2010 at 8:53 AM, <paul [dot] chavent [..] ...> wrote:
> Hello Peter.
>
> Thank you for your reply.
>
> I've the same error by removing the third param. Moreover, i don't see the declaration of the function whithout the "third" param.

Try to use tc.provides()->addOperation

The issue we're having is that for 'short notation' some of the
functions of the Service class are repeated in the TaskContext class.
note: *some*.

It seems like 'addOperation' for C functions is not one of them.

This *is* documented in the Doxygen API[1]. But it's clear now that
no-one is reading that anymore.

Peter

[1] http://www.orocos.org/stable/documentation/rtt/v2.x/api/html/classRTT_1_...

Hello Peter.Thank you for

Submitted by snrkiwi on Wed, 2010-12-08 14:08.

On Dec 8, 2010, at 03:54 , Peter Soetens wrote:

> On Wed, Dec 8, 2010 at 8:53 AM, <paul [dot] chavent [..] ...> wrote:
>> Hello Peter.
>>
>> Thank you for your reply.
>>
>> I've the same error by removing the third param. Moreover, i don't see the declaration of the function whithout the "third" param.
>
> Try to use tc.provides()->addOperation
>
> The issue we're having is that for 'short notation' some of the
> functions of the Service class are repeated in the TaskContext class.
> note: *some*.
>
> It seems like 'addOperation' for C functions is not one of them.
>
> This *is* documented in the Doxygen API[1]. But it's clear now that
> no-one is reading that anymore.

Hey!!! That is the Orocos Bible for some of us! I use it on a nearly daily basis ...
S

Hello Peter.Thank you for

Submitted by Charles Lesire-... on Wed, 2010-12-08 09:56.

On 08/12/2010 09:54, Peter Soetens wrote:
> On Wed, Dec 8, 2010 at 8:53 AM,<paul [dot] chavent [..] ...> wrote:
>> Hello Peter.
>>
>> Thank you for your reply.
>>
>> I've the same error by removing the third param. Moreover, i don't see the declaration of the function whithout the "third" param.
> Try to use tc.provides()->addOperation
>
> The issue we're having is that for 'short notation' some of the
> functions of the Service class are repeated in the TaskContext class.
> note: *some*.
>
> It seems like 'addOperation' for C functions is not one of them.
>
> This *is* documented in the Doxygen API[1]. But it's clear now that
> no-one is reading that anymore.
>
> Peter
>
> [1] http://www.orocos.org/stable/documentation/rtt/v2.x/api/html/classRTT_1_...
According to the API, you even need to create the Operation object
explicitely:

tc->addOperation(new Operation("foo",&foo, ClientThread))

Charles.

Hello Peter.Thank you for

Submitted by peter on Wed, 2010-12-08 10:52.

On Wednesday 08 December 2010 10:54:24 Charles Lesire-Cabaniols wrote:
> On 08/12/2010 09:54, Peter Soetens wrote:
> > On Wed, Dec 8, 2010 at 8:53 AM,<paul [dot] chavent [..] ...> wrote:
> >> Hello Peter.
> >>
> >> Thank you for your reply.
> >>
> >> I've the same error by removing the third param. Moreover, i don't see
> >> the declaration of the function whithout the "third" param.
> >
> > Try to use tc.provides()->addOperation
> >
> > The issue we're having is that for 'short notation' some of the
> > functions of the Service class are repeated in the TaskContext class.
> > note: *some*.
> >
> > It seems like 'addOperation' for C functions is not one of them.
> >
> > This *is* documented in the Doxygen API[1]. But it's clear now that
> > no-one is reading that anymore.
> >
> > Peter
> >
> > [1]
> > http://www.orocos.org/stable/documentation/rtt/v2.x/api/html/classRTT_1_
> > 1TaskContext.html
>
> According to the API, you even need to create the Operation object
> explicitely:
>
> tc->addOperation(new Operation("foo",&foo, ClientThread))

This can't work. The variant you're refering to is when you use the 'old' RTT
1.x style of first creating an operation object and then passing a reference to
it:

Operation<void(double)> foo_op("foo",&foo, ClientThread);
tc->addOperation(foo_op);

There is a bug in the Doxygen documentation though :) It should suggest to use
'provides()' instead of 'operations()'.

Peter

Hello Peter.Thank you for

Submitted by Charles Lesire-... on Wed, 2010-12-08 11:28.

On 08/12/2010 11:51, Peter Soetens wrote:
> On Wednesday 08 December 2010 10:54:24 Charles Lesire-Cabaniols wrote:
>> On 08/12/2010 09:54, Peter Soetens wrote:
>>> On Wed, Dec 8, 2010 at 8:53 AM,<paul [dot] chavent [..] ...> wrote:
>>>> Hello Peter.
>>>>
>>>> Thank you for your reply.
>>>>
>>>> I've the same error by removing the third param. Moreover, i don't see
>>>> the declaration of the function whithout the "third" param.
>>> Try to use tc.provides()->addOperation
>>>
>>> The issue we're having is that for 'short notation' some of the
>>> functions of the Service class are repeated in the TaskContext class.
>>> note: *some*.
>>>
>>> It seems like 'addOperation' for C functions is not one of them.
>>>
>>> This *is* documented in the Doxygen API[1]. But it's clear now that
>>> no-one is reading that anymore.
>>>
>>> Peter
>>>
>>> [1]
>>> http://www.orocos.org/stable/documentation/rtt/v2.x/api/html/classRTT_1_
>>> 1TaskContext.html
>> According to the API, you even need to create the Operation object
>> explicitely:
>>
>> tc->addOperation(new Operation("foo",&foo, ClientThread))
> This can't work. The variant you're refering to is when you use the 'old' RTT
> 1.x style of first creating an operation object and then passing a reference to
> it:

You should really tag as deprecated the functions that are RTT1.x-like
but whose use should be avoided!

Charles.

Hello Peter.Thank you for

Submitted by Polch on Wed, 2010-12-08 10:40.

Indeed, i think it is the only way to do it. But i don't know where you read it in the api doc Charles.

Peter, if i read the api doc for TaskContext::addOperation (http://people.mech.kuleuven.be/~orocos/pub/stable/documentation/rtt/v2.1... the doc doesn't match the signature, but no matter) or Service::addOperation (http://people.mech.kuleuven.be/~orocos/pub/stable/documentation/rtt/v2.1...), i don't see more information on how to use the addOperation method.

You seem to be annoyed that no one read the api doc, but i grep for addOperation in the TaskContext page and i don't found that this should work (or not) with c function from a TaskContext pointer.

I found very usefull to have the API doc and sorry if i'am blind.

Hello Peter.Thank you for

Submitted by Polch on Wed, 2010-12-08 10:38.

Indeed, i think it is the only way to do it. But i don't know where you read it in the api doc Charles.

Peter, if i read the api doc for TaskContext::addOperation (http://people.mech.kuleuven.be/~orocos/pub/stable/documentation/rtt/v2.1.x/api/html/classRTT_1_1TaskContext.html#a58498e0c313cd13b85fdc5c2d5fc70ff the doc doesn't match the signature, but no matter) or Service::addOperation (http://people.mech.kuleuven.be/~orocos/pub/stable/documentation/rtt/v2.1.x/api/html/classRTT_1_1Service.html#ad9268059997e35308c06edcb1fd9c31b), i don't see more information on how to use the addOperation method.

You seem to be annoyed that no one read the api doc, but i grep for addOperation in the TaskContext page and i don't found that this should work (or not) with c function from a TaskContext pointer.

I found very usefull to have the API doc and sorry if i'am blind.

Hello Peter.Thank you for

Submitted by peter on Wed, 2010-12-08 11:00.

On Wednesday 08 December 2010 11:38:23 paul [dot] chavent [..] ... wrote:
> Indeed, i think it is the only way to do it. But i don't know where you
> read it in the api doc Charles.
>
> Peter, if i read the api doc for TaskContext::addOperation
> (http://people.mech.kuleuven.be/~orocos/pub/stable/documentation/rtt/v2.1.
> x/api/html/classRTT_1_1TaskContext.html#a58498e0c313cd13b85fdc5c2d5fc70ff
> the doc doesn't match the signature, but no matter) or
> Service::addOperation
> (http://people.mech.kuleuven.be/~orocos/pub/stable/documentation/rtt/v2.1.
> x/api/html/classRTT_1_1Service.html#ad9268059997e35308c06edcb1fd9c31b), i
> don't see more information on how to use the addOperation method.
>
> You seem to be annoyed that no one read the api doc, but i grep for
> addOperation in the TaskContext page and i don't found that this should
> work (or not) with c function from a TaskContext pointer.
>
> I found very usefull to have the API doc and sorry if i'am blind.

It's the other way around: I was seeing things that weren't there. I'm looking
into it.

Peter

Hello Peter.Thank you for

Submitted by peter on Wed, 2010-12-08 13:24.

On Wednesday 08 December 2010 11:56:07 Peter Soetens wrote:
> On Wednesday 08 December 2010 11:38:23 paul [dot] chavent [..] ... wrote:
> > Indeed, i think it is the only way to do it. But i don't know where you
> > read it in the api doc Charles.
> >
> > Peter, if i read the api doc for TaskContext::addOperation
> > (http://people.mech.kuleuven.be/~orocos/pub/stable/documentation/rtt/v2.1
> > .
> > x/api/html/classRTT_1_1TaskContext.html#a58498e0c313cd13b85fdc5c2d5fc70f
> > f the doc doesn't match the signature, but no matter) or
> > Service::addOperation
> > (http://people.mech.kuleuven.be/~orocos/pub/stable/documentation/rtt/v2.1
> > . x/api/html/classRTT_1_1Service.html#ad9268059997e35308c06edcb1fd9c31b),
> > i don't see more information on how to use the addOperation method.
> >
> > You seem to be annoyed that no one read the api doc, but i grep for
> > addOperation in the TaskContext page and i don't found that this should
> > work (or not) with c function from a TaskContext pointer.
> >
> > I found very usefull to have the API doc and sorry if i'am blind.
>
> It's the other way around: I was seeing things that weren't there. I'm
> looking into it.

There's a fix on the master branch for this. The documented usage for C
functions was not working. I added a unit test and now it seems to behave as
expected. The syntax is:

tc.provides()->addOperation("name",&foo,ClientThread);

Thanks for reporting !

Peter

Hello Peter.Thank you for

Submitted by Charles Lesire-... on Wed, 2010-12-08 10:52.

On 08/12/2010 11:38, paul [dot] chavent [..] ... wrote:
> Indeed, i think it is the only way to do it. But i don't know where you read it in the api doc Charles.

The addOperation method can take an Operation object as an argument:
http://www.orocos.org/stable/documentation/rtt/v2.x/api/html/classRTT_1_...

> Peter, if i read the api doc for TaskContext::addOperation (http://people.mech.kuleuven.be/~orocos/pub/stable/documentation/rtt/v2.1... the doc doesn't match the signature, but no matter) or Service::addOperation (http://people.mech.kuleuven.be/~orocos/pub/stable/documentation/rtt/v2.1...), i don't see more information on how to use the addOperation method.
>
> You seem to be annoyed that no one read the api doc, but i grep for addOperation in the TaskContext page and i don't found that this should work (or not) with c function from a TaskContext pointer.
>
> I found very usefull to have the API doc and sorry if i'am blind.
>